1. Technical Field
Embodiments of the present invention relate to a dual band wearable antenna, more particularly to a wearable antenna having a dual band that relays communications between a wireless device implanted in the body and a wireless device outside the body.
2. Description of the Related Art
With the growing interest in the wireless body area network (WBAN), wireless RF communication for use near a human body or centering on a human body is increasing in importance. Such wireless RF communication can be combined not only with the WBAN, in which a device may be mounted on the human body such as by implanting the device into the body or wearing the device on the body to form a node with the human body, but also with wireless sensor networks, wireless personal area networks, and the like, to expand its application to various fields.
In the application fields mentioned above, various devices are being used for monitoring vital signs by way of medical equipment implanted inside a human body. Such medical equipment may operate by checking, for example, the heart rate, blood pressure, etc., and transmitting the results to an external device, and may employ an antenna for transmitting data wirelessly.
When a conventional body-implanted wireless device having an antenna communicates directly with a wireless device that is outside the body, the high dielectric rate of the human body may cause changes in the return loss properties of the antenna, resulting in problems of degraded performance or unwanted operation in actual practice. Moreover, other restraints such as low radiation efficiency, low power consumption, limited radiation power for avoiding interference with nearby medical devices, and the like, may impose limits in implementing direct communication with an external wireless device.